1. Field of the Invention
The invention relates generally to the devices and methods for introducing active chemical ingredients to a treatment chamber of an automated chemical vapor deposition system and creating protective films and coatings on organic and inorganic substrates by a chemical vapor deposition.
2. Description of Prior Art and Related Information
Many glass-based consumer products, such as beverage containers, food containers, sunglass lenses, automotive windshields and windows, require protective coating to guard against scratches, stains and breakage due to blunt impacts. Various techniques for creating protective films and coatings on substrates such as glass, silica based glass, and even metal oxide based steel are known in the art. Some of these known techniques include manual application of active chemical ingredients by hand and automated application by chemical vapor deposition process.
Manual application of active ingredients on a substrate is typically done by spraying chemical solutions onto a surface of the substrate by hand or by using a handheld machine. While manual application may produce an effective coating, such application is slow, labor intensive, creates safety concerns, and scales poorly for large volume applications. Moreover, the active ingredients used in creating films or coatings on substrates often require highly volatile and flammable organic solvents to aid in the application process, as the active ingredients generally do not provide an effective coating when applied to substrates in their pure form. During manual application by hand, chemical solutions can spill, be over sprayed onto the surface of the substrate, damage work surfaces and floors, and create a hazardous work environment. For instance, the organic solvents used with the active ingredients may evaporate into the surrounding air and create a health hazard to the technician performing the manual application. Because of these risks, the technician performing the manual application is required to wear personal protective equipments to avoid breathing in vapors. Further, the common occurrence of chemical spillage during manual applications increases the risks of releasing great amounts of harmful chemicals to the environment, damaging equipments and inventory, and creating fire and slip-and-fall injuries in the workplace.
To address the issue of releasing harmful solvent vapor associated with manual application of chemical solutions, some techniques in the prior art employ a vapor extraction system that confines solvent fumes by entirely performing the manual application inside an extraction booth. However, performing the manual application inside the extraction booth reduces scalability, increases the need for personal protective equipment for the technician, and greatly increases the risk of personal injury to the technician in the event that the safety measures implemented in the extraction system fail.
Some of the aforementioned problems can be overcome by automated chemical vapor deposition processes known in the art. Chemical vapor deposition processes greatly reduce the human labor involved in applying active ingredients onto the substrates, and in turn, reduce the labor costs and the risks of hazard to the technician and the environment. However, many chemical vapor deposition processes known in the art require applying the active ingredients onto the substrates under vacuum inside vacuum chambers. Vacuum chambers are typically slow in evacuating chemical vapors and limited in capacity, as there is a certain limitation to the maximum physical size of substrates that can be coated using chemical vapor deposition processes inside vacuum chambers. Thus, while the manual labor costs and the risk of releasing harmful vapors are reduced, the size limitation of vacuum chambers does not solve scalability problems, and in fact, dramatically reduces production capacity.
Yet, other known chemical vapor deposition techniques for creating films on substrates teach performing the chemical vapor deposition at atmospheric pressure and without the use of vacuum chambers, which address the issues of scalability, labor costs and vapor release. Such techniques are typically performed in room-sized application chambers that remain at atmospheric pressure throughout the vapor deposition process. These room-sized chambers provide the advantage of allowing high volume applications of active ingredients with minimal labor requirements. The operator of such chamber can load large amounts of large substrates into the chamber and apply film coating to every exposed surface with active ingredients in a relatively short amount of time. Typically, such operation can be completed under an hour. However, the operator of this type of chamber is required to carefully measure the precise quantities of the correct active ingredients, manually inject them into a chemical introduction system during the operation of the chamber and perform certain steps at very specific times during the process. When doing so, the operator must wear personal protective equipments to avoid breathing in toxic fumes and to protect against chemical spills, as these active ingredients are often flammable and stored in glass bottles. The fragility of glass bottles combined with the toxicity of the active ingredients present a significant hazard when the bottles are dropped or the contents are spilled. Additionally, the active ingredients used in such chemical vapor deposition processes are typically air sensitive. Thus, the operator must apply an inert gas blanket, such as nitrogen, when opening the bottles to reduce the decomposition rate of the active ingredients due to air exposure. Most users of this type of chamber do not have the necessary equipments to perform a nitrogen blanket. Further, even when a nitrogen blanket is used, some air exposure is unavoidable when operating such chambers.